本文使用沉浸邊界法來模擬昆蟲在非定常狀態下的飛行情形。使用沉浸邊界法之優點就是可以簡單的在卡氏座標中計算及表現複雜幾何外型的物體。文中會討論升力和阻力的生成機制，及詳細探討渦度場對於時間的變化，並討論兩個不同的座標系統（慣性座標系和非慣性座標系）相互之關係，最後與王[13]作一個比較及討論。而結果顯示非慣性座標下的結果比慣性座標的精確度要高。
接下來討論雷諾數及相位角的變化對升力和阻力所產生的影響，結果發現當雷諾數小於78.5時，昆蟲無法產生足夠的升力來支撐它的飛行，而當雷諾數增加，升力及阻力也會隨著增加；在相位角的變化中，討論三個不同的相位角，在延遲旋轉中，昆蟲無法產生足夠的升力來提供飛行所需的能量，而預先旋轉所產生的升力，卻比稱旋轉還大了百分之四十左右。

Abstract
This thesis reports the simulations of insect flight using the immersed boundary. The major advantage of the IBM is that the computations can be performed within the Cartesian framework to mimic the complex geometry of the insect wing. Both the inertial and non-inertial coordinate systems are adopted in the computations and the predicted lift and drag coefficients are examined. In comparisons with the benchmark solutions of Wang, the non-inertial frame simulation was observed to produce more accurate results than those generated by the inertial frame. When examining the predicted vorticity fields, the wake capture and delayed stall phenomena were captured by the present predictions
The influences of the Reynolds number and the phase differences on the lift and drag were also examined. The ranges of the Reynolds numbers investigated are from 78.5 to 314. It was shown that the insect can not generate enough lift force to support its flight when the Reynolds number was smaller than 78.5. The lift and drag were also shown to increase in tandem with the Reynolds number. The computations of the variations of the phase angles, , and , show that the delayed rotation produces the negative lift force. On the other hand, both the lift and drag forces generated by the advanced rotation are approximately 40% higher than those generated by the symmetric rotation.

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